An explosion of an electric tricycle killed seven people and injured 14 others in northwest China's Xinjiang Uygur Autonomous Region Thursday, local authorities said.

The accident occurred at about 10:30 a.m. on a bridge on the outskirts of Aksu City in southern Xinjiang, the autonomous regional government's information office said in a statement.

A suspect had been seized by police at the site and was being questioned, the statement said.

Local authorities were going all out to treat the injured people, it added.